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Valve Train:
Production high-performance pushrods have a hardened-steel insert tip in one end, and should be installed with this end up. The high-performance rocker arm has a raised letter “O” forged in the pallet end and a polished pallet. No. 3927142 valve springs should be installed at 1.70” height, and should have 110 lb. load at installed height for camshaft No. 3927140. New rocker arms and balls will burn sooner than run-in parts. If necessary to change a rocker and ball, always install a good used run-in rocker and ball. If good used ones are not available, move an intake rocker and ball over to the burned exhaust position and install the new parts on an intake position which runs cooler.

Oil Pump:
Weld pickup tube into body of pump. On lower end of pick up tube, some sort of flat round pickup shield similar to production should be used to keep from picking up air along with oil. Pickup height should be checked and adjusted to be 1/4 to 3/8” above oil pan bottom.

Oil Pan:
Modify as desired for increased capacity. Run semi-circular or flat Corvette tray baffle and some sort of horizontal baffle attached to the tower step of the oil pan to retard oil sloshing on brake stops. Production Z/28 302 engine oil pans have excellent baffling already built in, and have proven satisfactory in competition running one (1) quart over full. If available, a magnetic drain plug should be installed.

This Chevy line drawing shows how to install the available oil cooler, in this case on a Chevelle.

Oil Cooler:
If desired an oil cooler can be plumbed into the engine using No. 3157804 cooler now available. Adaptors to go in place of production oil filter and remote oil filters to take off, filter, cool and return oil to engine are available through our high performance and special equipment store. In all installations, at least 1/2” ID line should be used and the oil filtered just before it is returned to the engine to prevent contamination of engine bearings.

Oil Pressure Gauge:
Oil pressure gauge line to a mechanical gauge should be a minimum of 1/8” ID to get good gauge response and help detect any oil pressure losses quickly.

Cylinder Heads:
Production high-performance cylinder heads come equipped with 1.6” OD exhaust valve and 2.02” OD inlet valves. Improvements in overall performance can be obtained with the following head rework: Increase the circumference of valve seats to the outer edge of the valve face and narrow the seat by increasing the inner seat diameter with a 35 degree stone or cutter for exhaust and 25 degree cutter for inlet, leaving a .030” inlet seat and .050” exhaust seat. Remove the unused portion of the valve seat on the valve itself with a 20 degree backcut. This narrows the valve face which now matches the valve seat width in the head. Remove all ridges from combustion chambers. Port exhaust port out to maximum size and narrow and streamline the exhaust valve guide boss that protrudes into port. DO NOT shorten valve guide. Do the same for inlet ports. Use valve spring No. 3927142 at 1.7” installed height for cam No. 3927140, or other suitable dual valve spring. Use steel head gasket with aluminum paint for sealer, or a composition gasket without sealer. Torque head bolts to 65 ft.-lb. It is recommended that rocker arm studs be pinned to keep them from pulling out of the cylinder heads, or replaced by screw-in studs.